Cover for gun sights



. ril 23, 1929. L. PAuLus T AL -1,710,109

I COVER FOR our: SIGHTS Filed Feb. 5, 1924 IN VENTOR C/varlca lZRauLua y ,Eobarb K'dwolv ATTORNEY Patented Apr. 1929.

UNITED/STATES PATENT OFFICE;

amazes L. IPAULUB am) 301mm moon, or DAYTON, 01110. I

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"Application am February a, 1924. mm 80. 000,770.

Thisv invention relates to a cover for gun sights used on aircraft, and is designed to keep the front lensor cover glass of the sight clear ofa coating of oil, oil vapor,'mist, water, or thelike, which is otherwise'deposited by the slipstream when the airplane is in flight, or more particularlywhen it is being tuned up preparatorytotaking off, atwhich' time there is usuallysurplus water and oil thrown in the form of a spray by the propeller. r a 1 One of the principal objects of the invention is to provide a cover of a relatively simple construction having a sealing" fit on the end of the sight tube and adapted for rotation on an axis parallel to the axis of the sight tube out of range or vision through the tube and into a position where the action of the slipstream does not have any tendency to close the cover nor to place any undue load on its operating means.

Another object is to provide inconnection with the cover a means for yieldingly holding it in either of the two positions which it occupies.

In the drawing illustrating the invention,

Fig. 1 is a side view partly in section, and partly in elevation of a gun sight equipped with a cover of the present invention. An intermediate portion of the sight tube and cover-operating rod is bro en away.

Fig. 2 is an end view of the tube with the cover in place thereon. p

The invention is herein described as applied to gun sights, although it will appear in the course of the following-description that the various features of the cover adapt it for more or less general application to sighting devices wherever it is desired to provide similar protection. --for lenses or cover glasses.

The gun sight tube 1 wh ch 1s mounted n the plane usually at somepoint where it is subject to the slipstream.; has an eye piece 2 of suitably resilient material atone endand is provided with a lens or cover glass 3 1n its forward end; Other-lenses forming an optical system, it is" understood will be ineluded in the'intermediate portion of the tube-.. The lens}? is held in place in the end of the tube by-"a retainin ring 4 threaded or otherwise suitably hel upon the end of the tube. This ring has its outer face bevelledto provide a bevelled on tapered seat 5. -A sheet metal cover'6 of a concave form has an annular lip 7 of a similar inclination to the seat 5 to fit snugly and with a sealing fit thereon when the cover is in place. The

cover is riveted as at 8 to the forward end 9:

of an operating rod 10 extending lengthwise of the tube 1 to a point readil accessible to the observer at theinner en of thetube. The rod 10 is received in a bearing 11 provided inthe'retaining ring 4 on one side of the tube 1. It is also received in a bearing 12 provided in a ring 13 fitted on the tube 1 near the eye-piece 2. The bearings enable rotation of the rod with the cover on an axis parallel with the axis of the tube. The

rod 10 is bentoutwardly asshown at 14 to provide an operating arm for manually rocovering the end of the tube.

tating the cover 6 to and from its position *A compression spring 15 encircles the rod 10 and abuts at its 0 posite'ends the bearin 11 and a washer 16 iield in place on the rod 10 by a pin 17 so that the cover 6 is yieldingly urged inwardly toward more intimate contact with the seat 5 sealing the end of the tube and preventing accidental displacement. The spring also provides a frictional drag on the movement of the coverwhich serves to retain it in either of its adjusted positions, as it is important that the cover should not swing into the range of vision through the tube when an observation is being made. In this connection, it might also e noted that in the openin of the cover the bevelled end of the retaining ring 4 causes the cover to move bodily outwardly in riding over it and then moves inwardly at the limit of its movement. Similarly when the cover swin s back into place it moves bodil outwar ly in riding back over the bevel ed end of the ring 4.- and then rides inwardly into its fully closed position, aided somewhat by' the action of the spring 15. This feature coupled with the fact that the spring 15 gives a sealing fit of the cover on the tube as it urges the cover inwardly, pre vents accidental movement of the cover into or out of lace.

The sig t cover is normally in the position shown in Fig. 1 and just before aiming the tion out of range cover. The s ring serves to draw the cover into snug sealing contact covering the end of the tube.

We claim 1. In a sight device, a tube having a front lens or cover glass 1n the end thereof, a tapered seat at the outer end of said tube in front of said 'cover glass, a cover for the end of said tubehaving a face thereof to engage said taperedQseat to seal the end of said tube, said cover being rotatable edgewise to a position out of range of 'vision through'the tube and being caused. to move outwardly and invvardly in moving from open to closed position or vice versa in riding over said tapered seat, and spring means normally urging said cover inwardly.

2. In a sight device, a tube, having a front lens or cover glass in the end thereof, a securi member for said glass. forming a tapere d seat at-the forward slidable over said seat edgewise from a osiof sight through the tube to a position engagingsaid seat and covering end of said tube in front'of said cover glass, a concave cover the end of said tube, a manually rotatable rod for operating said cover to swin it into and out of position covering the en of said tube, and spring means for yieldingly urging said cover inwardly.

3. In a sight device for aircraft, a tube having a front lens or cover glass in the end thereo a'cover for the end of said tube to protect said lens, a bearing on the side of said tube, a rod rotatably received in said bearing extending lengthwise alongside the tube having one end connected with said cover and .Its other and bent outwardly-to provide an arm for manually operating said cover, anda spring acting between said hearing and said rod to urge said cover yieldingly inwardly-toward the end of said tube to effect a sealing contact when the tube is covered and its adjusted positions covering and uncoverin the tube.

n testimony whereof we aflix our signatures. v

i CHARLES L. PAULUS. :ROBERT KAUCH.

to hold said cover in either of 

